A variety of abnormal conditions, mishaps, accidents, etc., can cause disruption of high tension power lines by reason of damage or failure of one or more of the permanent towers. The ensuing interruption of power supply can have extremely serious consequences to both the public utility and its customers. For example, it is roughly estimated that the cost of service interruption on a main power line averages $500,000.00 per day. These interruptions and need for expedited service restoration operations are likely to occur in exceedingly rough and inaccessible terrain. In consequence, it may not be possible to utilize customary and requisite heavy duty equipment to erect conventional tower hardware. The attending problems are exacerbated by the need to provide temporary power line support structures displaced from the installed line to permit unobstructed access for repair of the damaged towers without risk of injury to life and property.
Emergency tower hardware has been proposed to provide temporary restoration of power service utilizing prefabricated units interconnectible at the site employing light duty installation equipment. Typically, assembled sections of such temporary towers are 100 or more feet in length and this poses problems and risks of serious injury while the tower is being uprighted onto its foundation. Proposals have been made for providing the lower end of the tower assembly with a fulcrum seatable in a concavity secured to the foundation. Such an arrangement is very hazardous for obvious reasons.